Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
during when
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase 'during when' is not correct in written English.
The correct phrase is 'during which'. For example: I will never forget the summer during which I finally decided to start my own business.
⚠ May contain grammatical issues
News & Media
Science
Wiki
Alternative expressions(20)
in its entirety
at all times
every inch of the way
in all sports
to the greatest degree feasible
every stage of the way
during after
in general
even while
areas
even as
during
all things considered
to the fullest possible extent
during the
in all senses of the word
in full measure
during which
entirely to the base
as long as
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
28 human-written examples
That cliché came to mind during "When Them," the assured, resonant duet Ms. Rosenblit created for herself and her longtime collaborator, the keenly expressive Addys Gonzalez.
News & Media
If rolling out the baby photos on the big screens during When We Were Young feels a bit mawkish, her Bond theme Skyfall and Set Fire to the Rain both sound gripping and dramatic.
News & Media
It was a journey I have repeated at intervals ever since, before and after the Olympics – but not during, when the authorities deemed it helpful to shut the station most convenient for the main stadium.
News & Media
To examine what happens during when apps go on sale, Distimo examined the 100 top grossing apps in the iPhone App Atore, iPad App Store and Android Market.
News & Media
Apparently the Google-only clause was only specific to the Canadian roll out and will be lifted during when the paywall launches worldwide on March 28th.
News & Media
The spinach plants were observed for 5 weeks during when the potted soils were watered at 2-day intervals and kept weed-free.
Human-verified similar examples from authoritative sources
Similar Expressions
31 human-written examples
This year, like last, Thanksgiving falls during Ramadan, when Muslims fast during daylight hours.
News & Media
They postulated that PaO2 rose during inflation when the alveoli were open and fell (during exhalation) when the alveoli collapsed [18].
During the Event S, the Esb layers appear during nighttime when E z is small.
Science
Eisenberg means during production, when he was shooting his scenes.
News & Media
(It is unavailable during holidays when he returns home).
News & Media
Expert writing Tips
Best practice
Replace "during when" with grammatically correct alternatives like "during which", "while", or "as" to ensure clarity and credibility in your writing.
Common error
Don't use "during when" because it's grammatically redundant. "During" already implies a time frame, and "when" introduces a clause, creating an unnecessary combination. Instead, use "during which" or rephrase the sentence using "while" or "as".
Source & Trust
84%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
Conjunction phrase, albeit grammatically questionable. Ludwig AI indicates that the phrase "during when" is incorrect, and usage should be avoided in formal writing. The primary function is to connect two events occurring simultaneously, but the construction is non-standard.
Frequent in
News & Media
41%
Science
41%
Wiki
7%
Less common in
Formal & Business
0%
Reference
0%
Encyclopedias
0%
Ludwig's WRAP-UP
While the phrase "during when" appears in various sources, including news, science, and wiki articles, it's generally considered grammatically incorrect. Ludwig AI suggests using alternatives such as "during which", "while", or "as" for improved clarity and grammatical accuracy. Although "during when" is common, especially in informal registers, it is not advisable in formal writing. Utilizing correct alternatives enhances the credibility and precision of your communication.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
while
A simpler and more direct conjunction to indicate simultaneous events.
during the time that
A more explicit and grammatically correct way to specify a period.
throughout the period when
Emphasizes the duration of the overlapping events.
in the course of which
A formal alternative to indicate what happens within a specific timeframe.
as
Indicates simultaneity, similar to 'while' but can also imply causality.
at the time when
Specifies a particular moment or point in time.
in the period that
Focuses on a specific span of time.
whilst
A slightly archaic synonym for 'while'.
as long as
Indicates a condition that extends for a period.
during which time
Another grammatically correct option to define a period.
FAQs
Is "during when" grammatically correct?
No, "during when" is generally considered grammatically incorrect. The word "during" already implies a period of time, making the addition of "when" redundant. You should use "during which" or rephrase the sentence.
What can I use instead of "during when"?
Better alternatives include "during which", "while", or "as", depending on the specific context of your sentence. These options provide clarity and grammatical correctness.
How do I properly use "during which" in a sentence?
"During which" is used to introduce a relative clause that specifies a period of time. For example, "The project lasted for three months, during which time we faced several challenges."
Why is "during when" considered redundant?
The word "during" already indicates that something is happening within a specific timeframe. Adding "when" is unnecessary because it duplicates the temporal reference, making the phrase awkward and grammatically unsound.
Editing plus AI, all in one place.
Stop switching between tools. Your AI writing partner for everything—polishing proposals, crafting emails, finding the right tone.
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
84%
Authority and reliability
2.8/5
Expert rating
Real-world application tested